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Physico-chemical characterization of 3-hydroxybutyrate with respect to its bioprotective effects
Kahanovská, Kristína ; Smilek, Jiří (referee) ; Sedláček, Petr (advisor)
The main aim of the work was to verify bio-protective properties of 3-hydroxybutyrate (3HB) in terms of its effect on protein denaturation (especially lipase) and determine the physicochemical characteristics of 3HB that could lead to the explanation of the mechanism of its protective effect. The literature search focused primarily on the mechanism of the protective effect of the compatible solutes. The 3HB belongs to the group of compatible solutes. The protective effect of the 3HB was monitored by Dynamic Light Scattering (DLS). As the other parameters of the aqueous solution 3HB were determined: the dependence of the surface tension on the concentration of the 3HB, the effect of different 3HB concentrations on the zeta potential of the lipase. Hydrophobic and hydrophilic character of the 3HB was characterized with the log Kow parameter. A simple method for quantity determination of the 3HB aqueous solution was optimized. The method is based on conversion of the 3HB into crotonic acid by reaction with sulphuric acid at higher temperatures and on subsequent psectrophotometric determination of the amount of crotonic acid.
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Ketózy u dojného skotu, jejich léčba a profylaxe
Hronová, Julie
Ketosis is considered the most common and economically very important metabolic disease in high producing dairy cows. At the onset of lactation, the energy metabolism of dairy cows is disturbed and they enter into a negative energy balance. The main symptom of ketosis is an increased concentration of ketone bodies in urine, milk and blood. Ketone bodies are composed of acetone, acetoacetic acid and β-hydroxybutyric acid, which is the highest in relation to ketone body composition. Clinical signs of ketosis are characterized by weight loss, decreased performance, impaired reproductive performance and the possibility of other metabolic diseases. Prevention is very important to avoid the development of ketosis and the large economic losses resulting from this disease. The basic preventive measure is proper nutritional management in the pre- and postnatal period.
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Vliv tělesné kondice dojnic na hladinu ketolátek v krvi
BEŇASOVÁ, Veronika
The aim of this diploma thesis is to evaluate the data about holstein dairy cow body condition at calving and to review its effect on ketones blood level and its relation to incidence of ketosis. The monitoring took place in a selected dairy farm from October 2017 to February 2019. Body condition of 280 cows was evaluated on the day of calving by assessing the body condition score (BCS) and later on 10 days in milk the blood level of B-hydroxybutyrate was measured. Furthermore, parity, body weight in calving day, body weight on 10 days in milk, content of milk fat and protein on 10 days in milk and milk yield on 10 days in milk were monitored. Average BCS of the herd was 3,7, the maximum measured BCS value was 5, the minimum was 2. Total incidence of ketosis on herd level was 21,07 % considering ketosis if BHB 1,0 mmol.l-1. 62,7 % of that was a subclinical form of ketosis while the remaining 37,3 % was the clinical form of ketosis. Correlation analysis of the relation between parity and level of BHB in blood showed positive correlation (r=0,15, p=0,00), when cows on higher lactation had higher level of blood BHB. Positive correlation between fat/protein ratio in milk and level of BHB in blood was evaluated by correlation analysis (r=0,31 , p=0,00). The BCS at calving and BHB level on 10 days in milk showed positive correlation (r=0,14 , p=0,02). As far as negative energy balance is taken into account, the positive correlation between BCS at calving and body weight loss was confirmed (r=0,17 , p=0,00). The fact that heavier cows and cows with higher BCS mobilise more body fat reserves was confirmed by positive correlation between the body weight at calving and the body weight loss (r=0,47, p=0,00) and between the body weight at calving and the fat/protein ratio in milk (r=0,27, p=0,00). Body weight at calving had provable positive impact on the milk yield (r=0,19, p=0,00).
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NITRIC OXIDE AND REACTIVE OXYGEN SPECIES IN ACUTE CORONARY SYNDROME
Šnorek, Michal ; Herget, Jan (advisor) ; Ošťádal, Petr (referee) ; Al-Hiti, Hikmet (referee)
In cardiology, there are different conditions associated with the release of free radicals in some forms of hypoxia, such as ventilatory hypoxia or reduced perfusion. The role of free radicals during hypoxia in cardiology is the key point of our interest. In presented thesis, we have focused on hypoxia-induced pulmonary vasoconstriction and acute myocardial ischemia. Hypoxic pulmonary vasoconstriction (HPV), an important physiological mechanism, is regulated by changes in the production of and interactions among reactive oxygen species (ROS). There is controversy, however, over whether HPV is mediated by an increase or a decrease in ROS production. Also, the role of nitric oxide (NO) in HPV remains unclear. Our results indicate that inhibition of HPV by the superoxide dismutase mimetic tempol does not depend on either NO production or a decrease in basal vascular tone. The effect of three-day fasting on cardiac ischemic tolerance was investigated in another experimental model. Short-term fasting conclusively decreases ROS production. Three-day fasting effectively protected rat hearts against major endpoints of acute ischemia-reperfusion injury. It prevented severe ventricular arrhythmias and reduced the extent of myocardial infarction. These beneficial effects can be linked to altered mitochondrial redox...
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Physico-chemical characterization of 3-hydroxybutyrate with respect to its bioprotective effects
Kahanovská, Kristína ; Smilek, Jiří (referee) ; Sedláček, Petr (advisor)
The main aim of the work was to verify bio-protective properties of 3-hydroxybutyrate (3HB) in terms of its effect on protein denaturation (especially lipase) and determine the physicochemical characteristics of 3HB that could lead to the explanation of the mechanism of its protective effect. The literature search focused primarily on the mechanism of the protective effect of the compatible solutes. The 3HB belongs to the group of compatible solutes. The protective effect of the 3HB was monitored by Dynamic Light Scattering (DLS). As the other parameters of the aqueous solution 3HB were determined: the dependence of the surface tension on the concentration of the 3HB, the effect of different 3HB concentrations on the zeta potential of the lipase. Hydrophobic and hydrophilic character of the 3HB was characterized with the log Kow parameter. A simple method for quantity determination of the 3HB aqueous solution was optimized. The method is based on conversion of the 3HB into crotonic acid by reaction with sulphuric acid at higher temperatures and on subsequent psectrophotometric determination of the amount of crotonic acid.
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